TW201616472A - Driver circuit with device variation compensation and operation method thereof - Google Patents

Abstract

A driver circuit with device variation compensation function and an operation method thereof are provided. The driver circuit includes a pull-up switch unit, an isolating switch and a pull-down switch unit. The first terminal of the pull-up switch unit is coupled to a first voltage. The second terminal of the pull-up switch unit is coupled to the output terminal of the driver circuit. The first terminal of the isolator switch is coupled to the second terminal of the pull-up switch unit. The first terminal of the pull-down switch unit is coupled to the second terminal of the isolator switch. The second terminal of the pull-down switch unit is coupled to a second voltage. The pull-down switch unit has device variation compensation function.

Description

Driving circuit with component variation compensation and operation method thereof

The disclosure relates to a driving circuit, and in particular to a driving circuit with component variation compensation and an operating method thereof.

A conventional gate driving circuit of a display panel uses an N-type thin film transistor (TFT). In order to continuously turn off the thin film transistor of the pixel on the scanning line (gate line), the gate driving circuit needs to keep the voltage of the scanning line (the gate voltage of the thin film transistor) at a low potential. In the conventional gate drive circuit, a pull-down circuit that provides a low potential needs to be continuously turned on, resulting in a continuous bias of the thin film transistor. Thin film transistors may exhibit characteristic drift phenomena (eg, characteristic degradation and/or drift of threshold voltage) under operating conditions that continue to be subjected to high voltage bias. The degradation of the characteristics of the thin film transistor will shorten its working life, and the drift of the threshold voltage (Vth) of the transistor will affect the reliability of the gate driving circuit.

The disclosed embodiments provide a driving circuit and an operating method thereof that can compensate for a threshold voltage variation of an element.

An embodiment of the present disclosure provides a driving circuit including a pull-up switch unit, an isolating switch, and a pull-down switch unit. The first end of the pull-up switch unit is coupled to the first voltage. The second end of the pull-up switch unit is coupled to the output end of the driving circuit. The first end of the isolating switch is coupled to the second end of the pull-up switch unit. The first end of the pull-down switch unit is coupled to the second end of the isolating switch. The second end of the pull-down switch unit is coupled to the second voltage. When the driving circuit operates in the initialization mode, the isolating switch is turned off, and the pull-down switching unit can sample the threshold voltage of the pull-down switching unit to obtain a pull-down threshold voltage value. When the driving circuit operates in the normal mode, the above-mentioned isolating switch is turned on, and the pull-down switching unit uses the cutoff voltage value to compensate the input voltage of the pull-down switch unit.

In an embodiment of the disclosure, the pull-down switch unit includes a pull-down switch and a pull-down switch compensation circuit. The first end of the pull-down switch is coupled to the second end of the isolating switch. The second end of the pull-down switch is coupled to the second voltage. The pull-down switch compensation circuit is coupled between the control end of the pull-down switch unit and the control end of the pull-down switch. When the driving circuit operates in the initialization mode, the pull-down switch compensation circuit samples the threshold voltage of the pull-down switch to obtain a pull-down threshold voltage value. When the driving circuit operates in the normal mode, the pull-down switch compensation circuit uses the pull-down threshold voltage value to compensate the input voltage of the pull-down switch.

In an embodiment of the disclosure, the pull-down switch compensation circuit includes a capacitor, a first switch, a second switch, and a third switch. First and second ends of the capacitor The terminals are respectively coupled to the control end of the pull-down switch unit and the control end of the pull-down switch. The first end and the second end of the first switch are respectively coupled to the third voltage and the second end of the capacitor. The first end and the second end of the second switch are respectively coupled to the second end of the capacitor and the first end of the pull-down switch. The first end and the second end of the third switch are respectively coupled to the first end of the capacitor and the second end of the pull-down switch.

In an embodiment of the disclosure, the pull-down switch compensation circuit includes a capacitor, a first switch, a second switch, and a third switch. The first end and the second end of the capacitor are respectively coupled to the control end of the pull-down switch unit and the control end of the pull-down switch. The first end and the second end of the first switch are respectively coupled to the third voltage and the second end of the capacitor. The first end and the second end of the second switch are respectively coupled to the second end of the capacitor and the first end of the pull-down switch. The first end and the second end of the third switch are respectively coupled to the first end and the fourth voltage of the capacitor. In an embodiment of the disclosure, the third voltage is a first system voltage and the fourth voltage is a second system voltage.

In an embodiment of the disclosure, the driving circuit further includes an isolation switch compensation circuit. The isolation switch compensation circuit is coupled to the control end of the isolation switch. When the driving circuit operates in the initialization mode, the isolation switch compensation circuit samples the threshold voltage of the isolation switch to obtain an isolation threshold voltage value. When the driving circuit operates in the normal mode, the isolation switch compensation circuit uses the isolation threshold voltage value to compensate the input voltage of the isolation switch.

In an embodiment of the disclosure, the above-described isolation switch compensation circuit includes a capacitor, a first switch, a second switch, and a third switch. The first end and the second end of the capacitor are respectively coupled to the control voltage and the control end of the isolating switch. First of the first switch The terminal and the second end are respectively coupled to the reference voltage and the second end of the capacitor. The first end and the second end of the second switch are respectively coupled to the second end of the capacitor and the first end of the isolating switch. The first end and the second end of the third switch are respectively coupled to the first end of the capacitor and the second end of the isolating switch.

In an embodiment of the disclosure, the isolation switch compensation circuit includes a first capacitor, a second capacitor, a first switch, a second switch, a third switch, and a fourth switch. The first end of the first capacitor is coupled to the control voltage. The first end and the second end of the second capacitor are respectively coupled to the second end of the first capacitor and the control end of the isolating switch. The first end and the second end of the first switch are respectively coupled to the reference voltage and the second end of the second capacitor. The first end and the second end of the second switch are respectively coupled to the second end of the second capacitor and the first end of the isolating switch. The first end and the second end of the third switch are respectively coupled to the first end of the second capacitor and the second end of the isolating switch. The first end and the second end of the fourth switch are respectively coupled to the first end and the second end of the first capacitor.

In an embodiment of the disclosure, the isolation switch compensation circuit includes a first capacitor, a second capacitor, a first switch, a second switch, and a third switch. The first end of the first capacitor is coupled to the control voltage. The first end and the second end of the second capacitor are respectively coupled to the second end of the first capacitor and the control end of the isolating switch. The first end and the second end of the first switch are respectively coupled to the reference voltage and the second end of the second capacitor. The first end and the second end of the second switch are respectively coupled to the first end of the second capacitor and the second end of the isolating switch. The first end and the second end of the third switch are respectively coupled to the first end and the second end of the first capacitor.

In an embodiment of the disclosure, the above driving circuit further includes an output Pull the switch. The first end of the output pull-down switch is coupled to the output of the drive circuit. The second end of the output pull-down switch is coupled to the second voltage.

In an embodiment of the disclosure, the driving circuit further includes a control unit. The input end of the control unit is coupled to the input of the drive circuit. The first output end and the second output end of the control unit are respectively coupled to the control end of the pull-up switch unit and the control end of the pull-down switch unit.

In an embodiment of the disclosure, the control unit includes a first transistor, a second transistor, a third transistor, and a fourth transistor. The first end of the first transistor is coupled to the first voltage. The second end of the first transistor is coupled to the control end of the pull-up switch unit. A control end of the first transistor is coupled to an input end of the driving circuit. The first end of the second transistor is coupled to the second end of the first transistor. The second end of the second transistor is coupled to the second voltage. The control end of the second transistor is coupled to the control end of the pull-down switch unit. The first end of the third transistor is coupled to the first voltage. The second end of the third transistor is coupled to the control end of the second transistor. The first end of the fourth transistor is coupled to the second end of the third transistor. The second end of the fourth transistor is coupled to the second voltage. A control end of the fourth transistor is coupled to an input end of the driving circuit.

An embodiment of the present disclosure provides a method of operating a drive circuit. The driving circuit includes a pull-up switch unit, an isolating switch and a pull-down switch unit. The first end and the second end of the pull-up switch unit are respectively coupled to the first voltage and the output end of the driving circuit, wherein the first voltage is the first system voltage. The first end of the isolating switch is coupled to the second end of the pull-up switch unit. The first end and the second end of the pull-down switch unit are respectively coupled to the second end of the isolating switch and the second voltage, wherein the second electric The voltage is the second system voltage. The operating method includes: turning off the isolation switch when the driving circuit operates in an initialization mode; sampling a threshold voltage of the pull-down switching unit to obtain a pull-down threshold voltage value when the driving circuit operates in the initialization mode; When the circuit operates in a normal mode, the isolation switch is turned on; and when the driving circuit operates in the normal mode, the pull-down threshold voltage value is used to compensate an input voltage of the pull-down switch unit.

In an embodiment of the disclosure, the pull-down switch unit includes a pull-down switch. The first end of the pull-down switch is coupled to the second end of the isolating switch. The second end of the pull-down switch is coupled to the second voltage. The operating method includes: sampling a threshold voltage of the pull-down switch to obtain the pull-down threshold voltage value when the driving circuit operates in the initialization mode; and using the pull-down threshold voltage value when the driving circuit operates in the normal mode Compensate for the input voltage of the pull-down switch.

In an embodiment of the disclosure, the pull-down switch unit further includes a capacitor. The first end and the second end of the capacitor are respectively coupled to the control end of the pull-down switch unit and the control end of the pull-down switch. The step of sampling the threshold voltage of the pull-down switch includes: coupling the first end and the second end of the capacitor to the second end and the third voltage of the pull-down switch respectively during charging of the initialization mode; During the discharge of the initialization mode, the first end of the capacitor is coupled to the second end of the pull-down switch, and the second end of the capacitor is coupled to the first end and the control end of the pull-down switch.

In an embodiment of the disclosure, the pull-down switch unit further includes a capacitor. The first end and the second end of the capacitor are respectively coupled to the control end of the pull-down switch unit and the control end of the pull-down switch. The step of sampling the threshold voltage of the pull-down switch The method includes: during the charging of the initialization mode, coupling the second end and the first end of the capacitor to the third voltage and the fourth voltage respectively; and during the discharging of the initialization mode, coupling the first end of the capacitor The fourth voltage is connected, and the second end of the capacitor is coupled to the first end of the pull-down switch and the control end.

In an embodiment of the present disclosure, the operating method further includes: sampling the threshold voltage of the isolation switch to obtain an isolation threshold voltage when the driving circuit operates in the initialization mode; and when the driving circuit operates in the normal state In the mode, the isolation threshold voltage is used to compensate the input voltage of the isolation switch.

In an embodiment of the disclosure, the driving circuit further includes a capacitor. The first end and the second end of the capacitor are respectively coupled to the control voltage and the control end of the isolating switch. The step of sampling the threshold voltage of the isolation switch includes: coupling the second end and the first end of the capacitor to the first reference voltage and the second reference voltage respectively during the charging of the initialization mode; and During the discharge of the mode, the first end of the capacitor is coupled to the second end of the isolating switch, and the second end of the capacitor is coupled to the first end and the control end of the isolating switch.

In an embodiment of the disclosure, the driving circuit further includes a capacitor. The first end and the second end of the capacitor are respectively coupled to the control voltage and the control end of the isolating switch. The step of sampling the threshold voltage of the isolation switch includes: coupling the second end and the first end of the capacitor to the first reference voltage and the second reference voltage respectively during the charging of the initialization mode; and During the discharge of the mode, the first end of the capacitor is coupled to the second end of the isolating switch, and the second end of the capacitor is coupled to the first reference voltage and the control end of the isolating switch.

In an embodiment of the disclosure, the operating method further includes: when the driving circuit operates in the initialization mode, pulling down a voltage of an output end of the driving circuit to the second voltage.

Based on the above, the driving circuit and the operating method thereof according to the embodiments of the present disclosure can sample the threshold voltage of the internal pull-down switch by using the pull-down switching unit. When the driving circuit operates in the normal mode, the pull-down switching unit can compensate the input voltage of the pull-down switching unit according to the sampled threshold voltage. Therefore, the driving circuit and the operating method thereof according to the embodiments of the present disclosure can compensate for the threshold voltage variation of the component.

In order to make the disclosure more apparent, the following embodiments are described in detail with reference to the accompanying drawings.

100‧‧‧ drive circuit

110‧‧‧Pull switch unit

120‧‧‧Isolation switch

130‧‧‧ Pull-down switch unit

131‧‧‧ pull-down switch

132, 133‧‧‧ pull-down switch compensation circuit

139‧‧‧Control end

140‧‧‧Control unit

141‧‧‧First transistor

142‧‧‧second transistor

143‧‧‧ Third transistor

144‧‧‧4th transistor

211‧‧‧ Capacitance

221‧‧‧First switch

222‧‧‧second switch

223, 224‧‧‧ third switch

450‧‧‧Output pull-down switch

500‧‧‧ drive circuit

560‧‧‧Isolation switch compensation circuit

561‧‧‧Capacitor, second capacitor

562‧‧‧First switch

563‧‧‧second switch

564‧‧‧ third switch

565‧‧‧Capacitor, first capacitor

566‧‧‧fourth switch

P1‧‧‧Charging period

P2‧‧‧discharge period

P3‧‧‧Charging period

P4‧‧‧Discharge period

PI‧‧‧Initial mode

PI1‧‧‧ first period

PI2‧‧‧ second period

S110~S150‧‧‧Steps

V0‧‧‧ control voltage

V1‧‧‧ first voltage

V2‧‧‧second voltage

V3‧‧‧ control voltage

V4‧‧‧ voltage

V5~V11‧‧‧ control signal

V _c1 , V _c2 ‧‧‧ voltage

Vdd‧‧‧ system voltage

-Vdd‧‧‧negative system voltage

Vin‧‧‧ input

Vout‧‧‧ output

V _p2 ‧‧‧ voltage

Vss‧‧‧ Grounding voltage

FIG. 1A is a block diagram showing a circuit of a driving circuit according to an embodiment of the invention.

FIG. 1B is a schematic flow chart showing an operation method of a driving circuit according to an embodiment of the present disclosure.

FIG. 2 is a circuit diagram showing the driving circuit of FIG. 1A according to an embodiment of the present disclosure.

FIG. 3 is a timing diagram illustrating the control signal shown in FIG. 2 according to an embodiment of the present disclosure.

4 is a diagram illustrating the power of the driving circuit of FIG. 1A according to another embodiment of the present disclosure. Road map.

FIG. 5 is a block diagram showing a circuit of a driving circuit according to another embodiment of the disclosure.

FIG. 6 is a circuit diagram illustrating the driving circuit of FIG. 5 according to an embodiment of the present disclosure.

FIG. 7 is a timing diagram illustrating the control signal shown in FIG. 6 according to an embodiment of the present disclosure.

FIG. 8 is a circuit diagram illustrating the driving circuit of FIG. 5 according to another embodiment of the present disclosure.

FIG. 9 is a timing diagram illustrating the control signal shown in FIG. 8 according to an embodiment of the present disclosure.

FIG. 10 is a circuit diagram illustrating the driving circuit of FIG. 5 according to still another embodiment of the present disclosure.

The term "coupled" as used throughout the specification (including the scope of the patent application) may be used in any direct or indirect connection. For example, if the first device is described as being coupled to the second device, it should be construed that the first device can be directly connected to the second device, or the first device can be connected through other devices or some kind of connection means. Connected to the second device indirectly. In addition, wherever possible, the elements and/ Components/components that use the same reference numbers or use the same terminology in different embodiments The steps can refer to the relevant instructions.

The driving circuit can generate a corresponding output signal according to the level of the input signal to drive the load circuit. In the case where the output of the drive circuit is maintained at the same level for a long time, its internal transistor needs to be constantly biased. Taking a push-pull output circuit as an example, in a case where the push-pull output signal of the driving circuit is maintained at a low logic level, a pull-down transistor (for example, an N-type transistor) of the push-pull output circuit in the driving circuit is used. The bias voltage needs to continue at a high logic potential. A pull-down transistor that provides a low output potential causes a phenomenon in which its transistor characteristics may drift due to continuous application of a high voltage (for example, characteristic degradation and/or drift of a threshold voltage).

For another example, the gate driving circuit of the display panel may use an N-type thin film transistor (TFT). In order to continuously turn off the thin film transistor of the pixel on the scanning line (gate line), the gate driving circuit needs to keep the voltage of the scanning line (the gate voltage of the thin film transistor) at a low potential. In the conventional gate drive circuit, a pull-down circuit that provides a low potential needs to be continuously turned on, resulting in a continuous bias of the thin film transistor. Under continuous high voltage bias operating conditions, thin film transistors may exhibit characteristic drift phenomena (eg, characteristic degradation and/or drift of threshold voltage). The degradation of the characteristics of the thin film transistor will shorten its working life, and the drift of the threshold voltage (Vth) of the transistor will affect the reliability of the gate driving circuit.

To solve this problem, some embodiments will utilize multiple sets of pull-down circuits/components to share the pull-down function to reduce the duty cycle of the pull-down circuit/component. However, as the operating time is lengthened, these pull-down circuits/components still produce a phenomenon of threshold voltage drift. Furthermore, process drift may occur during the fabrication of the driver circuit. Process drift can alter the characteristics of the transistor, such as mutating the threshold voltage of the transistor. How to improve the reliability of the drive circuit and effectively smooth the effects caused by the variation of the threshold voltage between components is a problem that must be solved.

The following embodiments will describe a driving circuit with component variation compensation and a method of operating the same. The driver circuit can directly compensate component characteristics to compensate for the threshold voltage variation of the pull-down switch (such as a thin film transistor or other switching element). This driver circuit can have a threshold voltage compensation function to improve reliability and accuracy.

FIG. 1A is a block diagram showing a circuit of a driving circuit 100 according to an embodiment of the present disclosure. The drive circuit 100 includes a pull-up switch unit 110, an isolation switch 120, a pull-down switch unit 130, and a control unit 140. The first end of the pull-up switch unit 110 is coupled to the first voltage V1. The second end of the pull-up switch unit 110 is coupled to the output terminal Vout of the driving circuit 100. The first end of the isolating switch 120 is coupled to the second end of the pull-up switch unit 110. The first end of the pull-down switch unit 130 is coupled to the second end of the isolating switch 120. The second end of the pull-down switch unit 130 is coupled to the second voltage V2. The first voltage V1 and the second voltage V2 may be voltages of any level, wherein the first voltage V1 is greater than the second voltage V2. For example, but not limited to, the first voltage V1 may be a first system voltage (eg, system voltage Vdd or other voltage), and the second voltage V2 may be a second system voltage (eg, a ground voltage Vss or Is other voltage). In another embodiment, the first voltage V1 may be a clock signal, and the second voltage V2 may be a second system voltage (eg, a ground voltage Vss or other voltage). In other embodiments, this second system voltage (second voltage V2) may be any fixed voltage, ground voltage, or negative voltage greater than 0V.

The isolating switch 120 is controlled by a control voltage V3. When the drive circuit 100 operates in the normal mode, the isolation switch 120 is turned on. When the drive circuit 100 is operated in the initialization mode, the isolation switch 120 is turned off.

Control unit 140 is any input stage circuit, such as a differential input pair circuit, a shift register, a multiplexor, or other input stage. The input end of the control unit 140 is coupled to the input terminal Vin of the driving circuit 100. The first output end and the second output end of the control unit 140 are respectively coupled to the control end of the pull-up switch unit 110 and the control end 139 of the pull-down switch unit 130. In the normal mode, the isolation switch 120 is conductive. According to the level of the input terminal Vin, the control unit 140 can correspondingly control the pull-up switch unit 110 and the pull-down switch unit 130 to jointly generate a signal of the output terminal Vout in a push-pull manner.

When the driving circuit 100 operates in the initialization mode, the pull-down switching unit 130 samples the threshold voltage (Vth) of the pull-down switching unit 130 to obtain a pull-down threshold voltage value. The drive circuit 100 can sample the threshold voltage of its internal pull-down switch using the pull-down switch unit 130. Therefore, when the driving circuit 100 operates in the normal mode, the pull-down switching unit 130 can use the pull-down threshold voltage value to compensate the input voltage of the pull-down switching unit 130.

The method of operation of the drive circuit 100 is described herein. FIG. 1B is a schematic flow chart showing an operation method of a driving circuit according to an embodiment of the present disclosure. Step S110 can determine the operation mode of the drive circuit 100. 1A and 1B can be cross-referenced. When it is determined in step S110 that the driving circuit 100 is operated in the initialization mode, the off-isolation is turned on. Off 120 (step S120), and sampling the threshold voltage of the pull-down switch unit 130 with the compensation function to obtain a first threshold voltage value (step S130). When it is determined in step S110 that the driving circuit 100 is operating in the normal mode, the isolation switch 120 is turned on (step S140), and the input voltage of the pull-down switching unit 130 having the compensation function is compensated using the first threshold voltage value (step S150).

FIG. 2 is a schematic circuit diagram of the driving circuit 100 of FIG. 1A according to an embodiment of the present disclosure. In the embodiment shown in FIG. 2, the control unit 140 includes a first transistor 141, a second transistor 142, a third transistor 143, and a fourth transistor 144. The first end of the first transistor 141 is coupled to a third voltage (a first system voltage, such as a system voltage Vdd or other fixed voltage). The second end of the first transistor 141 is coupled to the control end of the pull-up switch unit 110. The control end of the first transistor 141 is coupled to the input terminal Vin of the driving circuit 100. The first end of the second transistor 142 is coupled to the second end of the first transistor 141. The second end of the second transistor 142 is coupled to a second voltage (a second system voltage, such as a ground voltage Vss or other fixed voltage). The control end of the second transistor 142 is coupled to the control terminal 139 of the pull-down switch unit 130. The first end of the third transistor 143 is coupled to a third voltage (eg, system voltage Vdd). The second end of the third transistor 143 is coupled to the control end of the second transistor 142 and the control end 139 of the pull-down switch unit 130. The control terminal of the third transistor 143 is controlled by the voltage V4. The voltage V4 can be a clock signal or a bias voltage of a fixed level. The first end of the fourth transistor 144 is coupled to the second end of the third transistor 143. The second end of the fourth transistor 144 is coupled to a second voltage (eg, a ground voltage Vss). The control terminal of the fourth transistor 144 is coupled to the input terminal Vin of the driving circuit 100.

In the embodiment shown in FIG. 2, the pull-down switch unit 130 includes a pull-down switch 131 and a pull-down switch compensation circuit 132. The first end of the pull-down switch 131 is coupled to the second end of the isolating switch 120. The second end of the pull-down switch 131 is coupled to a second voltage (a second system voltage, such as a ground voltage Vss or other fixed voltage). The pull-down switch compensation circuit 132 is coupled between the control terminal 139 of the pull-down switch unit 130 and the control terminal of the pull-down switch 131. When the driving circuit 100 operates in an initialization mode (for example, the initialization mode PI shown in FIG. 3), the pull-down switch compensation circuit 132 can sample the threshold voltage (Vth) of the pull-down switch 131 to obtain a pull-down threshold voltage value. When the drive circuit 100 operates in a normal mode (such as the normal mode PN shown in FIG. 3), the pull-down switch compensation circuit 132 compensates the input voltage of the pull-down switch 131 using the pull-down threshold voltage value.

In the embodiment shown in FIG. 2, the pull-down switch compensation circuit 132 includes a capacitor 211, a first switch 221, a second switch 222, and a third switch 223. The first end and the second end of the capacitor 211 are respectively coupled to the control end 139 of the pull-down switch unit 130 and the control end of the pull-down switch 131. The first end and the second end of the first switch 221 are respectively coupled to a third voltage (eg, system voltage Vdd) and a second end of the capacitor 211. The first end and the second end of the second switch 222 are respectively coupled to the second end of the capacitor 211 and the first end of the pull-down switch 131. The first end and the second end of the third switch 223 are respectively coupled to the first end of the capacitor 211 and the second end of the pull-down switch 131.

FIG. 3 is a timing diagram illustrating the control signal shown in FIG. 2 according to an embodiment of the present disclosure. The initialization mode PI shown in Fig. 3 can be performed before the normal mode PN. In other embodiments, the initialization mode PI can be in each frame (Frame) of Vin Do it before starting. Referring to FIG. 2 and FIG. 3, when the driving circuit 100 operates in the initialization mode PI, the control voltage V3 turns off the isolation switch 120. In the charging period P1 of the initialization mode PI, the control signals V5 and V7 respectively turn on the first switch 221 and the third switch 223, and the control signal V6 turns off the second switch 222. Therefore, during the charging period P1, the first switch 221 and the third switch 223 that are turned on can respectively couple the first end and the second end of the capacitor 211 to the second end of the pull-down switch 131 and the third voltage (for example, the system voltage Vdd). At this time, the potential difference between the system voltage Vdd and the second end of the pull-down switch 131 is stored in the capacitor 211.

During the discharge period P2 of the initialization mode PI, the control signals V6 and V7 respectively turn on the second switch 222 and the third switch 223, and the control signal V5 turns off the first switch 221. Therefore, during the discharge period P2, the third switch 223 that is turned on can couple the first end of the capacitor 211 to the second end of the pull-down switch 131, and the second switch 222 that is turned on can couple the second end of the capacitor 211 to the pull-down switch. The first end of 131. At this time, the pull-down switch 131 is connected to a diode-connected transistor, so that the capacitor 211 is discharged. The charge of the capacitor 211 is discharged to the ground voltage Vss via the second switch 222 and the pull-down switch 131 until the gate-source voltage of the pull-down switch 131 is approximately equal to the threshold voltage (Vth) of the pull-down switch 131. Therefore, the threshold voltage of the pull-down switch 131 can be stored in the capacitor 211. That is, if the voltage of the control terminal 139 of the pull-down switch unit 130 is V _p2 , the voltage of the control terminal of the pull-down switch 131 is V _c1 , and the threshold voltage of the pull-down switch 131 is V _th1 , the voltage difference between the two ends of the capacitor 211 is V _C1 -V _p2 =V _th1 .

When the drive circuit 100 operates in the normal mode PN, the control voltage V3 causes the isolation switch 120 to be turned on. At this time, the drain current I _{d of the} pull-down switch 131 = K (V _c1 - V _th1 ) ² = K [(V _p2 + V _th1 ) - V _th1 ] ² = K (V _p2 ) ² , where K is a constant. Therefore, the driving circuit 100 shown in FIG. 2 can improve/eliminate the variation effect of the pull-down threshold voltage value V _th1 of the pull-down switch 131. That is, the pull-down switch compensation circuit 132 shown in FIG. 2 can sample the pull-down threshold voltage value V _th1 of the pull-down switch 131 in the initialization mode PI, and then use the pull-down threshold voltage value V _th1 to compensate the pull-down switch unit 130 in the normal mode PN. The input voltage (the control terminal voltage V _{c1 of the} pull-down switch 131).

The embodiment of the drive circuit 100 shown in FIG. 1A should not be limited to the manner shown in FIG. 2. For example, FIG. 4 is a circuit diagram illustrating the driving circuit 100 of FIG. 1A according to another embodiment of the present disclosure. The embodiment shown in FIG. 4 can be analogized with reference to the related description of FIG. 2 and FIG. 3. In the embodiment shown in FIG. 4, the drive circuit 100 further includes an output pull-down switch 450. The first end of the output pull-down switch 450 is coupled to the output terminal Vout of the driving circuit 100. The second end of the output pull-down switch 450 is coupled to a second voltage (a second system voltage, such as a ground voltage Vss or other fixed voltage). The output pull-down switch 450 is controlled by the control voltage V0. When the driving circuit 100 operates in the initialization mode PI, the output pull-down switch 450 is turned on to pull the voltage of the output terminal Vout of the driving circuit 100 to a second voltage (for example, the ground voltage Vss). Therefore, outputting the pull-down switch 450 in the initialization mode PI can ensure that the voltage of the output terminal Vout of the driving circuit 100 is maintained at a low logic level. When the drive circuit 100 operates in the normal mode PN, the output pull-down switch 450 is turned off to avoid affecting the normal operation of the drive circuit 100.

In the embodiment shown in FIG. 4, the pull-down switch unit 130 includes a pull-down switch. 131 and pull-down switch compensation circuit 133. The pull-down switch compensation circuit 133 includes a capacitor 211, a first switch 221, a second switch 222, and a third switch 224. The first end and the second end of the capacitor 211 are respectively coupled to the control end 139 of the pull-down switch unit 130 and the control end of the pull-down switch 131. The first end and the second end of the first switch 221 are respectively coupled to a third voltage (a first system voltage, such as a system voltage Vdd or other fixed voltage) and a second end of the capacitor 211. The first end and the second end of the second switch 222 are respectively coupled to the second end of the capacitor 211 and the first end of the pull-down switch 131. The first end and the second end of the third switch 224 are respectively coupled to the first end of the capacitor 211 and the fourth voltage (the second system voltage, such as the ground voltage Vss or other fixed voltage).

When the drive circuit 100 operates in the initialization mode PI, the control voltage V3 turns off the isolation switch 120. In the charging period P1 of the initialization mode PI, the control signals V5 and V7 respectively turn on the first switch 221 and the third switch 224, and the control signal V6 turns off the second switch 222. Therefore, during the charging period P1, the first switch 221 and the third switch 224 that are turned on can couple the second end of the capacitor 211 and the first end to a third voltage (eg, system voltage Vdd) and a fourth voltage (eg, ground voltage Vss). ). At this time, the potential difference between the system voltage Vdd and the ground voltage Vss is stored in the capacitor 211.

During the discharge period P2 of the initialization mode PI, the control signals V6 and V7 respectively turn on the second switch 222 and the third switch 224, and the control signal V5 turns off the first switch 221. Therefore, during the discharge period P2, the turned-on third switch 224 can couple the first end of the capacitor 211 to the fourth voltage (eg, the ground voltage Vss), and the turned-on second switch 222 can couple the second end of the capacitor 211 to the pull-down. The first end of the switch 131. At this time, the pull-down switch 131 is connected to a transistor in the form of a diode, so that the capacitor 211 is discharged. Therefore, the threshold voltage of the pull-down switch 131 can be stored in the capacitor 211. That is, the voltage difference across the capacitor 211 is V _c1 - V _p2 = V _th1 .

When the drive circuit 100 operates in the normal mode PN, the control voltage V3 causes the isolation switch 120 to be turned on. At this time, the drain current I _{d of the} pull-down switch 131 = K (V _c1 - V _th1 ) ² = K [(V _p2 + V _th1 ) - V _th1 ] ² = K (V _p2 ) ² , where K is a constant. Therefore, the driving circuit 100 shown in FIG. 4 can improve/eliminate the variation effect of the pull-down threshold voltage value V _th1 of the pull-down switch 131.

FIG. 5 is a block diagram showing a circuit of a driving circuit 500 according to another embodiment of the disclosure. The driving circuit 500 includes a pull-up switch unit 110, an isolation switch 120, a pull-down switch unit 130, a control unit 140, and an isolation switch compensation circuit 560. The pull-up switch unit 110, the isolating switch 120, the pull-down switch unit 130 and the control unit 140 shown in FIG. 5 can be analogized with reference to the related description of FIG. 1A to FIG. 4, and therefore will not be described again.

In the embodiment shown in FIG. 5, the isolating switch compensation circuit 560 is coupled to the control terminal of the isolating switch 120. When the driving circuit 500 operates in the initialization mode, the isolation switch compensation circuit 560 can sample the threshold voltage of the isolation switch 120 to obtain the isolation threshold voltage value V _th2 . When the drive circuit 500 operates in the normal mode, the isolation switch compensation circuit 560 can compensate the input voltage of the isolation switch 120 using the isolation threshold voltage value _Vth2 . Therefore, when the driving circuit 500 operates in the normal mode, the isolation switch compensation circuit 560 can also use the isolation threshold voltage value V except that the pull-down switching unit 130 can use the pull-down threshold voltage value V _th1 to compensate the input voltage of the pull-down switching unit 130. _Th2 goes to compensate for the input voltage of the isolating switch 120.

FIG. 6 is a circuit diagram illustrating the driving circuit 500 of FIG. 5 according to an embodiment of the present disclosure. The driving circuit 500 shown in FIG. 6 includes a pull-up switch unit 110, an isolation switch 120, a pull-down switch unit 130, a control unit 140, an output pull-down switch 450, and an isolation switch compensation circuit 560. The pull-down switch unit 130 and the control unit 140 can be analogized with reference to the related description of FIG. 2 to FIG. 3, and the output pull-down switch 450 shown in FIG. 6 can be analogized with reference to the related description of FIG. 4, and therefore will not be described again. In the embodiment shown in FIG. 6, the pull-down switch unit 130 includes a pull-down switch 131 and a pull-down switch compensation circuit 132. In another embodiment, the pull-down switch compensation circuit 132 shown in FIG. 6 may be replaced with the pull-down switch compensation circuit 133 shown in FIG.

In the embodiment shown in FIG. 6, the isolation switch compensation circuit 560 includes a capacitor 561, a first switch 562, a second switch 563, and a third switch 564. The first end and the second end of the capacitor 561 are respectively coupled to the control voltage V3 and the control end of the isolating switch 120. The first end and the second end of the first switch 562 are respectively coupled to a first reference voltage (a second system voltage, such as a ground voltage Vss or other fixed voltage) and a second end of the capacitor 561. The first end and the second end of the second switch 563 are respectively coupled to the second end of the capacitor 561 and the first end of the isolating switch 120. The first end and the second end of the third switch 564 are respectively coupled to the first end of the capacitor 561 and the second end of the isolating switch 120.

FIG. 7 is a timing diagram illustrating the control signal shown in FIG. 6 according to an embodiment of the present disclosure. The initialization mode PI shown in Fig. 7 can be performed before the normal mode PN. In other embodiments, the initialization mode PI can be performed before the Vin of each frame (Frame) is started. The embodiment shown in FIG. 7 can be analogized with reference to the related description of FIG. Referring to FIG. 6 and FIG. 7, when the driving circuit 500 operates in the first period PI1 of the initialization mode PI, the isolation switch compensation circuit 560 can sample the threshold voltage of the isolation switch 120 to obtain the isolation threshold voltage value V _th2 . When the driving circuit 500 operates in the second period PI2 of the initialization mode PI, the pull-down switch compensation circuit 132 can sample the threshold voltage of the pull-down switch 131 to obtain the pull-down threshold voltage value V _th1 . When the driving circuit 500 operates in the normal mode PN, the pull-down switch compensation circuit 132 can compensate the input voltage of the pull-down switch 131 using the pull-down threshold voltage value V _th1 , and the isolation switch compensation circuit 560 can compensate the isolation switch 120 using the isolation threshold voltage value V _{th2 .} Input voltage. Regarding the operation details of the second period PI2 of the initialization mode PI and the operation details of the normal mode PN, please refer to the descriptions of the initialization mode PI and the normal mode PN described with reference to FIGS. 2 to 4, and thus will not be described again.

Referring to FIG. 6 and FIG. 7, in the charging period P3 of the first period PI1 of the initialization mode PI, the control signals V8 and V10 respectively turn on the first switch 562 and the third switch 564, and the control signal V9 turns off the second switch 563. . Therefore, during the charging period P3, the first switch 562 and the third switch 564 that are turned on can respectively couple the second end of the capacitor 561 and the first end to the first reference voltage (the second system voltage, such as the ground voltage Vss or other fixed Voltage) and a second reference voltage (eg, a negative system voltage provided by control voltage V3, -Vdd). At this time, the potential difference between the ground voltage Vss and the negative system voltage -Vdd is stored in the capacitor 561.

During the discharge period P4 of the first period PI1 of the initialization mode PI, the control signals V9 and V10 respectively turn on the second switch 563 and the third switch 564, and the control signal V8 turns off the first switch 562. Therefore, during the discharge period P4, the third switch 564 that is turned on can couple the first end of the capacitor 561 to the second end of the isolating switch 120, and the second switch 563 that is turned on can couple the second end of the capacitor 561 to the isolating switch 120. The first end. At this time, the isolation switch 120 is connected to a diode-connected transistor, so that the capacitor 561 is discharged. The charge of the capacitor 561 is discharged to the negative system voltage -Vdd via the second switch 563 and the isolation switch 120 until the gate-source voltage of the isolation switch 120 is approximately equal to the threshold voltage _{Vth2 of the} isolation switch 120. Therefore, the isolation threshold voltage value V _{th2 of the} isolation switch 120 can be stored in the capacitor 561. That is, if the voltage at the control terminal of the pull-down switch 131 is V _c2 , the voltage difference across the capacitor 561 is V _{c2 -} V3 = V _th2 .

When the drive circuit 500 operates in the normal mode PN, the control voltage V3 causes the isolation switch 120 to be turned on. Drain current isolation switch 120 _{I d = K (V c2 -V} th2) 2 = K [(V3 + V th2) -V th2] 2 = K (V3) 2, where K is a constant. Therefore, the driving circuit 500 shown in FIG. 6 can improve/eliminate the variation effect of the isolation threshold voltage value V _th2 of the isolation switch 120. Further, the drain current I _{d of the} pull-down switch 131 = K (V _c1 - V _th1 ) ² = K [(V _p2 + V _th1 ) - V _th1 ] ² = K(V _p2 ) ² , where K is a constant. Therefore, the driving circuit 100 shown in FIG. 6 can improve/eliminate the variation effect of the pull-down threshold voltage value V _th1 of the pull-down switch 131. That is, the isolation switch compensation circuit 560 and the pull-down switch compensation circuit 132 shown in FIG. 2 can respectively sample the isolation threshold voltage value V _{th2 of the} isolation switch 120 and the pull-down threshold voltage value V _th1 of the pull-down switch 131 in the initialization mode PI, and then In the normal mode PN, the isolation threshold voltage value V _th2 and the pull-down threshold voltage value V _th1 are used to compensate the input voltage of the isolation switch 120 and the input voltage of the pull-down switch unit 130, respectively.

The embodiment of the drive circuit 500 shown in FIG. 5 should not be limited to the manner shown in FIG. For example, FIG. 8 is a circuit diagram illustrating the driving circuit 500 of FIG. 5 according to another embodiment of the present disclosure. The embodiment shown in FIG. 8 can be analogized with reference to the related description of FIG. 6 and FIG. In the embodiment shown in FIG. 8 , the isolation switch compensation circuit 560 includes a first capacitor 565 , a second capacitor 561 , a first switch 562 , a second switch 563 , a third switch 564 , and a fourth switch 566 . The first end of the first capacitor 565 is coupled to the control voltage V3. The first end and the second end of the second capacitor 561 are respectively coupled to the second end of the first capacitor 565 and the control end of the isolating switch 120. The first end and the second end of the first switch 562 are respectively coupled to a reference voltage (a second system voltage, such as a ground voltage Vss or other fixed voltage) and a second end of the second capacitor 561. The first end and the second end of the second switch 563 are respectively coupled to the second end of the second capacitor 561 and the first end of the isolating switch 120. The first end and the second end of the third switch 564 are respectively coupled to the first end of the second capacitor 561 and the second end of the isolating switch 120. The first end and the second end of the fourth switch 566 are respectively coupled to the first end and the second end of the first capacitor 565.

FIG. 9 is a timing diagram illustrating the control signal shown in FIG. 8 according to an embodiment of the present disclosure. The embodiment shown in FIG. 9 can be analogized with reference to the related description of FIG. 7, and therefore will not be described again. Referring to FIGS. 8 and 9, the control signal V11 turns off the fourth switch 566 during the charging period P3 of the first period PI1 of the initialization mode PI. The control signal V11 turns on the fourth switch 566 during the discharge period P4 of the first period PI1 of the initialization mode PI. Therefore, the negative system voltage -Vdd provided by the control voltage V3 can be transmitted to the first terminal of the second capacitor 561. During the charging period P3, the second end and the first end of the second capacitor 561 are respectively coupled to the first reference voltage (the second system voltage, such as the ground voltage Vss or other fixed voltage) and the second reference voltage (eg, the negative system voltage). -Vdd). During the discharge period P4, the first end of the second capacitor 561 is coupled to the second end of the isolating switch 120, and the second end of the second capacitor 561 is coupled to the first end of the isolating switch 120 (at this time, the second system voltage, For example, a fixed voltage greater than 0V, a ground voltage Vss or a negative fixed voltage) and a control terminal of the isolating switch 120. After the end of the discharge period P4, the voltage difference across the second capacitor 561 is V _{c2 -} V3 = V _th2 . When the driving circuit 500 PN normal mode of operation, the drain current of the isolation switch 120 _{I d = K (V c2 -V} th2) 2 = K [(V3 + V th2) -V th2] 2 = K (V3) 2 , where K is a constant. Therefore, the driving circuit 500 shown in FIG. 8 can improve/eliminate the variation effect of the isolation threshold voltage value V _th2 of the isolation switch 120.

FIG. 10 is a circuit diagram illustrating the driving circuit 500 of FIG. 5 according to still another embodiment of the present disclosure. In the embodiment shown in FIG. 10, the isolation switch compensation circuit 560 includes a first capacitor 565, a second capacitor 561, a first switch 562, a third switch 564, and a fourth switch 566. The embodiment shown in FIG. 10 can be analogized with reference to the related descriptions of FIG. 8 and FIG. 9, and therefore will not be described again. Different from the embodiment shown in FIG. 8, the second switch 563 shown in FIG. 8 is omitted in the embodiment shown in FIG.

Referring to FIG. 9 and FIG. 10, in the previous operation, the fourth switch 566 once short-circuits both ends of the first capacitor 565 such that the voltage difference across the first capacitor 565 is zero. During the charging period P3 of the first period PI1 of the initialization mode PI, the control signal V11 turns off the fourth switch 566, the control signals V8 and V10 turn on the first switch 562 and the third switch 564, and the control voltage V3 is pulled down to the negative system. Voltage - Vdd. The negative system voltage -Vdd is applied to the first terminal of the second capacitor 561 via the first capacitor 565. The ground voltage Vss is applied to the second end of the second capacitor 561 via the first switch 562. Therefore, the second capacitor 561 is charged such that the voltage difference across the first capacitor 565 is approximately Vdd. At this time, since the gate-source voltage (the voltage difference between the gate and the source) of the isolation switch 120 is greater than the isolation threshold voltage value V _th2 of the isolation switch 120, the isolation switch 120 is turned on. Because the third switch 564, the isolating switch 120 and the output pull-down switch 450 are turned on, the second capacitor 561 is discharged to reduce the voltage difference between the two ends of the second capacitor 561, that is, the gate-source voltage of the isolating switch 120 is lowered. When the gate-source voltage of the isolation switch 120 is not greater than the isolation threshold voltage value V _th2 , the isolation switch 120 is turned off, so that the second capacitor 561 stops discharging. At this point, the isolation threshold voltage value V _{th2 of the} isolation switch 120 is sampled/saved into the second capacitor 561.

During the discharge period P4 of the first period PI1 of the initialization mode PI, the control signals V8 and V10 turn off the first switch 562 and the third switch 564 to store the isolation threshold voltage value _Vth2 in the second capacitor 561. The control signal V11 turns on the fourth switch 566, so the voltage difference across the first capacitor 565 can be reset to zero. After the end of the discharge period P4, the voltage difference across the second capacitor 561 is V _th2 . When the driving circuit 500 PN normal mode of operation, the drain current of the isolation switch 120 _{I d = K (V c2 -V} th2) 2 = K [(V3 + V th2) -V th2] 2 = K (V3) 2 , where K is a constant. Therefore, the driving circuit 500 shown in FIG. 10 can improve/eliminate the variation effect of the isolation threshold voltage value V _th2 of the isolation switch 120.

In summary, the driving circuit and the operating method thereof according to the above embodiments can use the pull-down switch unit 130 to sample the threshold voltage of the internal pull-down switch 131. When the driving circuit operates in the normal mode, the pull-down switch unit 130 can be based on The sampled threshold voltage is used to compensate for the input voltage of the pull-down switch unit 130. Therefore, the driving circuit and the operating method thereof according to the embodiments of the present disclosure can compensate for the threshold voltage variation of the component.

The present disclosure has been disclosed in the above embodiments, but it is not intended to limit the disclosure, and any person skilled in the art can make some changes and refinements without departing from the spirit and scope of the disclosure. The scope of protection of this disclosure is subject to the definition of the scope of the appended claims.

100‧‧‧ drive circuit

110‧‧‧Pull switch unit

120‧‧‧Isolation switch

130‧‧‧ Pull-down switch unit

131‧‧‧ pull-down switch

132‧‧‧ Pull-down switch compensation circuit

139‧‧‧Control end

140‧‧‧Control unit

141‧‧‧First transistor

142‧‧‧second transistor

143‧‧‧ Third transistor

144‧‧‧4th transistor

211‧‧‧ Capacitance

221‧‧‧First switch

222‧‧‧second switch

223‧‧‧third switch

V1‧‧‧ first voltage

V3‧‧‧ control voltage

V4‧‧‧ voltage

V5~V7‧‧‧ control signal

V _c1 ‧‧‧ voltage

Vdd‧‧‧ system voltage

Vin‧‧‧ input

Vout‧‧‧ output

V _p2 ‧‧‧ voltage

Vss‧‧‧ Grounding voltage

Claims (19)

A driving circuit includes: a pull-up switch unit, the first end of which is coupled to a first voltage, the second end of the pull-up switch unit is coupled to an output end of the driving circuit; and an isolating switch, the first The second end of the pull-up switch unit is coupled to the second end of the isolating switch, and the second end of the pull-down switch unit is coupled to a second voltage Wherein when the driving circuit is operated in an initialization mode, the isolating switch is off, the pull-down switching unit samples a threshold voltage of the pull-down switching unit to obtain a pull-off threshold voltage value; and when the driving circuit operates in a normal mode When the isolating switch is turned on, the pull-down switch unit uses the pull-down threshold voltage value to compensate an input voltage of the pull-down switch unit. The driving circuit of claim 1, wherein the pull-down switch unit comprises: a pull-down switch, the first end of which is coupled to the second end of the isolating switch, the second end of the pull-down switch is coupled to the a second voltage; and a pull-down switch compensation circuit coupled between the control end of the pull-down switch unit and the control end of the pull-down switch, wherein when the drive circuit operates in the initialization mode, the pull-down switch compensation circuit samples the Pulling a threshold voltage of the pull-down switch to obtain the pull-down threshold voltage value; and when the driving circuit operates in the normal mode, the pull-down switch compensation circuit uses the pull-down threshold voltage value to compensate an input of the pull-down switch Voltage. The driving circuit of claim 2, wherein the pull-down switch compensation circuit comprises: a capacitor, wherein the first end and the second end are respectively coupled to the control end of the pull-down switch unit and the control end of the pull-down switch a first switch, the first end and the second end are respectively coupled to a third voltage and a second end of the capacitor, wherein the third voltage is a first system voltage; and a second switch is first The second end is coupled to the second end of the capacitor and the first end of the pull-down switch, and the third end is coupled to the first end of the capacitor and the first end The second end of the pull-down switch. The driving circuit of claim 2, wherein the pull-down switch compensation circuit comprises: a capacitor, wherein the first end and the second end are respectively coupled to the control end of the pull-down switch unit and the control end of the pull-down switch a first switch, the first end and the second end are respectively coupled to a third voltage and a second end of the capacitor; and a second switch, the first end and the second end are respectively coupled to the capacitor a first end and a first end of the pull-down switch; and a third switch, the first end and the second end are respectively coupled to the first end of the capacitor and a fourth voltage, wherein the third voltage is first The system voltage, and the fourth voltage is the second system voltage. The driving circuit of claim 1, further comprising: an isolating switch compensation circuit coupled to the control end of the isolating switch, wherein the isolating switch compensating circuit samples when the driving circuit operates in an initializing mode An isolation voltage value is obtained by a threshold voltage of the isolation switch; and when the driving circuit operates in a normal mode, the isolation switch compensation circuit uses the isolation threshold voltage value to compensate an input voltage of the isolation switch. The driving circuit of claim 5, wherein the isolating switch compensation circuit comprises: a capacitor, wherein the first end and the second end are respectively coupled to a control voltage and a control end of the isolating switch; The first end and the second end of the switch are respectively coupled to a reference voltage and a second end of the capacitor, wherein the reference voltage is a second system voltage; and a second switch is coupled to the first end and the second end respectively The second end of the capacitor is connected to the first end of the capacitor and the first end of the capacitor is coupled to the first end of the capacitor and the second end of the isolating switch. The driving circuit of claim 6, wherein the isolating switch compensation circuit comprises: a first capacitor, the first end of which is coupled to a control voltage; and a second capacitor, the first end and the second end The first end of the first capacitor and the second end of the first switch are respectively coupled to a reference voltage and the first end a second end of the second capacitor; a first switch and a second end respectively coupled to the second end of the second capacitor and the first end of the isolating switch; a third switch, the first The first end and the second end are respectively coupled to the first end of the second capacitor and the second end of the isolating switch; and the fourth end is coupled to the first end of the first capacitor One end and the second end. The driving circuit of claim 6, wherein the isolating switch compensation circuit comprises: a first capacitor, the first end of which is coupled to a control voltage; and a second capacitor, the first end and the second end The second end of the first capacitor is coupled to the control end of the second switch; the first end and the second end are respectively coupled to a reference voltage and a second end of the second capacitor; a second switch, the first end and the second end are respectively coupled to the first end of the second capacitor and the second end of the isolating switch; and a third switch, the first end and the second end are respectively coupled Connected to the first end and the second end of the first capacitor. The driving circuit of claim 1, further comprising: an output pull-down switch, the first end of which is coupled to the output end of the driving circuit, and the second end of the output pull-down switch is coupled to the second voltage . For example, the driving circuit described in claim 1 further includes: a control unit having an input end coupled to the input end of the driving circuit, a first output end and a second output end of the control unit being respectively coupled to the control end of the pull-up switch unit and the pull-down switch unit Control terminal. The driving circuit of claim 10, wherein the control unit comprises: a first transistor, the first end of which is coupled to a third voltage, and the second end of the first transistor is coupled to the Pulling up the control end of the switch unit, and the control end of the first transistor is coupled to the input end of the drive circuit; a second transistor having a first end coupled to the second end of the first transistor, The second end of the second transistor is coupled to the second voltage, and the control end of the second transistor is coupled to the control end of the pull-down switch unit; a third transistor is coupled to the first end a third voltage, the second end of the third transistor is coupled to the control end of the second transistor; and a fourth transistor is coupled to the second end of the third transistor. The second end of the fourth transistor is coupled to the second voltage, and the control end of the fourth transistor is coupled to the input end of the driving circuit. An operation method of a driving circuit, the driving circuit includes a pull-up switch unit, an isolating switch and a pull-down switch unit, wherein the first end and the second end of the pull-up switch unit are respectively coupled to a first voltage and the driving An output end of the circuit, the first voltage is a first system voltage, the first end of the isolating switch is coupled to the second end of the pull-up switch unit, and the first end and the second end of the pull-down switch unit are respectively coupled To the second end of the isolating switch and a second voltage, the second voltage is a second system voltage, The operation method includes: when the driving circuit operates in an initialization mode, turning off the isolation switch; when the driving circuit operates in the initialization mode, sampling a threshold voltage of the pull-down switch unit to obtain a pull-off threshold voltage value; The driving circuit is turned on when the driving circuit operates in a normal mode; and when the driving circuit operates in the normal mode, the pull-down threshold voltage value is used to compensate an input voltage of the pull-down switching unit. The operating method of the driving circuit of claim 12, wherein the pull-down switch unit comprises a pull-down switch, the first end of the pull-down switch is coupled to the second end of the isolating switch, and the second end of the pull-down switch The operating method includes: when the driving circuit operates in the initializing mode, sampling a threshold voltage of the pull-down switch to obtain the pull-down threshold voltage value; and when the driving circuit operates in the In the normal mode, the pull-down threshold voltage is used to compensate for an input voltage of the pull-down switch. The operating method of the driving circuit of claim 13, wherein the pull-down switch unit further comprises a capacitor, wherein the first end and the second end of the capacitor are respectively coupled to the control end of the pull-down switch unit and the pull-down The step of sampling the threshold voltage of the pull-down switch includes: connecting the first end and the second end of the capacitor to the second end of the pull-down switch respectively during a charging of the initialization mode a third voltage, wherein the third voltage is the first system voltage; During a discharge of the initialization mode, the first end of the capacitor is coupled to the second end of the pull-down switch, and the second end of the capacitor is coupled to the first end and the control end of the pull-down switch. The operating method of the driving circuit of claim 13, wherein the pull-down switch unit further comprises a capacitor, wherein the first end and the second end of the capacitor are respectively coupled to the control end of the pull-down switch unit and the pull-down The step of sampling the threshold voltage of the pull-down switch includes: during a charging of the initialization mode, coupling the second end of the capacitor and the first end to a third voltage and a fourth a voltage, wherein the third voltage is the first system voltage, and the fourth voltage is the second system voltage; and during a discharge of the initialization mode, the first end of the capacitor is coupled to the fourth voltage, And coupling the second end of the capacitor to the first end and the control end of the pull-down switch. The operating method of the driving circuit of claim 12, further comprising: sampling a threshold voltage of the isolating switch to obtain an isolation threshold voltage when the driving circuit operates in the initializing mode; and when the driving When the circuit operates in the normal mode, the isolation threshold voltage is used to compensate an input voltage of the isolation switch. The operating circuit of the driving circuit of claim 16, wherein the driving circuit further comprises a capacitor, wherein the first end and the second end of the capacitor are respectively coupled to a control voltage and a control end of the isolating switch, Sampling the isolation switch The step of the threshold voltage includes: coupling a first reference voltage and a second reference voltage to the second end and the first end of the capacitor, wherein the first reference voltage is the first a second system voltage, wherein the second reference voltage is a negative system voltage; and during a discharge of the initialization mode, coupling the first end of the capacitor to the second end of the isolating switch, and causing the second of the capacitor The end is coupled to the first end of the isolation switch and the control end. The operating circuit of the driving circuit of claim 16, wherein the driving circuit further comprises a capacitor, wherein the first end and the second end of the capacitor are respectively coupled to a control voltage and a control end of the isolating switch, The step of sampling the threshold voltage of the isolating switch includes: coupling a second reference voltage and a first reference voltage to a first reference voltage and a second reference voltage respectively during a charging of the initializing mode; During a discharge of the initialization mode, the first end of the capacitor is coupled to the second end of the isolating switch, and the second end of the capacitor is coupled to the first reference voltage and the control end of the isolating switch. The operating method of the driving circuit of claim 12, further comprising: when the driving circuit operates in the initialization mode, pulling down a voltage of an output end of the driving circuit to the second voltage.